Turquoise in Matrix
Hydrated phosphate of copper and aluminium (CuAl6(PO4)4(OH)8·4H2O)
Rock Type: mineral

Physical Properties
Hardness: 5-6 (Mohs), Color: sky blue to blue-green, Luster: waxy to subvitreous, Crystal structure: Triclinic (usually massive), Specific Gravity: 2.6-2.9
Formation & Geological History
Formed through the infiltration of moisture through alumina-rich rocks in the presence of copper and phosphate, usually in arid, volcanic, or sedimentary environments.
Uses & Applications
Predominantly used as a gemstone in jewelry, decorative carvings, and as a popular collector specimen in its raw matrix form.
Geological Facts
Turquoise is one of the oldest known gemstones, used by Ancient Egyptians and Native Americans for over 5,000 years. The 'robins egg blue' color is highly prized, caused by copper content; iron content makes it greener.
Field Identification & Locations
Identify by its unique blue-green color within a tan or white host rock (matrix). Often found in the Southwestern USA, Iran, and China. In the field, look for bright blue veins in weathered volcanic rocks.
Identified on: 4/13/2026
Mode: Standard